The sister could be bullying Naruto out of envy. If Naruto has some special abilities or talents that she doesn't, she might be jealous and lash out at him.
It could also be his boisterous personality. Naruto is very outgoing and sometimes a bit of a troublemaker in his attempts to get attention. This might annoy some of the more reserved or studious kids at school, leading them to bully him as a way to try and make him conform or be quiet.
Here are some recommendations for novels about bullying sister-con sisters: 1. " Sister-spoiling Devil 2: The person who bullied his sister was shaved bald and had the word 'scumbag' tattooed on his forehead. He would carry it with him for life. He had to work hard and rely on his aunt." This novel told the story of a sister-con brother who took revenge on the person who bullied her in order to protect his sister. Please note that the novels recommended above may contain some fictional plots and characters. They are only for entertainment and reference.
One possible reason could be to protect her. Naruto might believe that by leaving, he can draw danger away from his sister. For example, if there are powerful enemies targeting him, he doesn't want his sister to get caught in the crossfire.
One way it could be developed is that his sister might be jealous of Naruto's growing popularity or skills. Maybe she feels overshadowed and starts to bully him by spreading false rumors about him in the village. This could lead to Naruto feeling more isolated and misunderstood, even as he tries to prove himself.
If such a fanfiction exists, one possible reason could be a mind - control situation. Maybe an enemy uses some powerful genjutsu to make Naruto believe his sister is a threat, causing him to kill her accidentally. Another reason could be a misinformation plot where Naruto is tricked into thinking his sister has committed some unforgivable crime against the village.
In the Naruto series, Naruto doesn't have a biological sister in the original story. So in this fanfiction, the author probably creates a new character to be his sister. It could be an original character with unique abilities and a complex backstory that leads to the situation where Naruto dies by her hand.
Maybe his sister is always favored by their parents, making Naruto feel left out and thus develop hatred.
One possible reason could be jealousy. Maybe the sister is more favored by the villagers or has some special abilities that Naruto feels overshadow his own. This could lead to a sense of envy and ultimately hatred.
One reason could be that he's under a lot of stress. Maybe he's facing a powerful enemy and the pressure is getting to him. So he snaps at everyone without realizing it.
Here are some novel recommendations about two brothers bullying their sister: 1. "Good girl! Call Me Older Sister ": This novel tells the love story between an older sister and a younger brother. The younger brother was in love with the older sister, and the older sister had always been oppressed by the younger brother and had to cook for him. The plot of this short story was compact and the writing was smooth. 2. " Quickly Wear the Little Koi Fish: Super Tempting After the Villain Becomes Evil ": This novel tells the story of a sweet love story between an older sister and her younger brother. Although it was not explicitly mentioned that the younger brother bullied the older sister, the story showed the older sister's protection and love for the younger brother. The above are the recommended novels based on the search results provided. I hope they can meet your needs.